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In the present article, a heat-treated nano-clay-composite was fabricated by stir-casting to improve high-cycle bending fatigue properties of AlSiCu aluminum alloys, which have been widely used in engine cylinder-heads. For such an objective, after ball milling of nano-clay-particles with micro-copper-particles, these coated particles were added to the aluminum melt and cylindrical specimens were stir-casted. Then, fully-reversed stress-controlled fatigue testing was performed on standard samples. In addition, the fracture surface was examined by the field-emission scanning electron microscopy to find failure mechanisms. Obtained results showed that reinforcements, including nano-clay-particles and the heat treatment increased the fatigue lifetime, at least 9%. Such an improvement in the fatigue lifetime was 125% under low values of the stress level. Due to have a proper distribution of nano-particles in the aluminum matrix, the scatter-band for the fatigue lifetime was narrower in the heat-treated nano-composite. The endurance fatigue limit was also improved 30% at 106 cycles, for the heat-treated nano-composite, comparing to the base material. The brittle fracture was observed due to have cleavage and quasi-cleavage marks on the fracture surface for both materials. Micro-cracks were initiated and propagated from Si and intermetallics phases.

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Aim: Acute myeloid leukemia (AML) is a heterogeneous disease in pathogenesis and response to therapy. Nucleotide excision repair (NER) pathway has a major role in the elimination of genotoxic effects of chemotherapeutic agents. We aimed to clarify the effects of selected variants of XPD, XPC, ERCC5 and ERCC1 genes on the outcomes of induction therapy. Materials & methods: The prevalence of NER genetic variants was evaluated in 67 subjects with AML and their effects on clinical outcomes were analyzed by χ2 test. Results: The XPD 751 Lys variant was associated with improved response to chemotherapy compared with XPD 751 Gln and Lys/Gln variants (p = 0.023; odds ratio: 4.5; 95% CI: 1.14–17.73). There were no associations between other genotypes and any outcomes. Conclusion: Current findings suggest that XPD Lys751Gln variant could be considered as a prognostic factor in AML.

Background and Aims: Myeloid cell leukemia-1 (Mcl-1) plays a pivotal role in the survival of hematologic and solid tumors, and is known as a substantial oncogene. Studies have demonstrated the altered expression of Mcl-1 has been linked to malignancy development and poor prognosis. In this research, we have studied the expression of Mcl-1 mRNA in myelodysplastic syndrome (MDS) patients and determined association with clinico-pathological factors, MDS subgroups as well as international prognostic scoring system. Materials and Methods: The relative level of Mcl-1 was determined by real time quantitative real-time polymerase chain reaction and gene expression normalized to Glyceraldehyde-3-phosphate dehydrogenase. Results: Results indicated amplification of mRNA encoding Mcl-1 in 100% of the cases. The higher level of Mcl-1 existed in MDS patients compared with the healthy controls but there was no statistically difference of Mcl-1 expression between these groups. Fold change in gene expression was higher in advanced stage MDS, high risk MDS, cases with >5% blast and LDH >400 to their corresponding groups. In addition, the correlation between gene expression and cytogenetic prognostic subgroups was statistically significant (p=0.043). Conclusions: In the present study, we showed that Mcl-1 is expressed in MDS independent of the World Health Organization subgroup and international prognostic scoring system. Therefore, Mcl-1 may be up-regulated already in early stages of leukemogenesis.